1. Field of the Invention
The present invention relates to an apparatus for treating or processing a substrate, such as a semiconductor wafer or a glass substrate, etc., with the so-called an ashing process under a condition of reduced pressure.
2. Description of Related Art
For conducting processes under a reduced pressure condition, such as an ashing process, upon a substrate with high efficiency, a processing apparatus has already been known which is provided with a load lock chamber within a processing chamber thereof.
The procedure in accordance with this processing apparatus is that, while a substrate is treated in the processing chamber, another substrate to be treated next is placed into the load lock chamber for waiting, in which chamber the pressure is also reduced down to the same level as that of the processing chamber. When the process or treatment within the processing chamber is completed, the unprocessed substrate waiting in the load lock chamber is brought into the processing chamber, while the substrate processed in the processing chamber is taken out therefrom, and then the processing chamber is insulated from the load lock chamber by a shutter. After that, another shutter insulating the load lock chamber from an outer space is opened so as to bring out the processed substrate from the load lock chamber and also to bring a new substrate into the load lock chamber.